About LGS 3D                  About LGS 2D

Variational geometric solver LGS 3D, developed and supported by LEDAS, is offered for licensing to all CAD/CAM/CAE software development companies at an affordable price. It is used as a parametric engine for 3D modeling, assembly design, kinematics analysis, history-free geometry editing, and other applications. LGS 3D is a cross-platform software package. It is a set of binary libraries running under all 32- and 64-bit Windows, Linux, *BSD, AIX, HP-Unix, Sun Solaris and other OS. Coded in C++, LGS 3D has a C-based API that allows integration into a broad range of software applications.

LGS 3D supports creation and modification of the geometric models by means of either explicit or implicit constraints. Typical geometric objects are points, lines, circles, planes, cylinders, spheres, parametric curves, surfaces and swept surfaces. Objects can be fixed in the absolute coordinate system or with respect to each other (last feature is provided by so-called rigid sets of objects). The supported set of geometric constraints includes logical constraints between geometric entities (coincidence, parallelism, tangency, etc.) and dimensional constraints that specify the required values for given distances, angles or radii. LGS 3D moves and rotates objects to positions where all constraints are satisfied with minimal possible transformations of initial configuration. Other LGS 3D functions implement advanced features of CAD/CAM/CAE systems - moving under constraints, diagnostics of over- and under-defined parts of a model, engineering variables and equations, help points and tolerance management.

A sample 3D modeling application called Lege’n’d 3D is available as a free download with a set of representative examples of different 3D assemblies. This application can be used by anyone to test functionality, robustness and performance of LGS 3D. It was created with the Open CASCADE open-source application framework. The source code of Lege’n’d 3D is available under special request.

Current version is LGS 3D 1.5

New version 1.5 of LGS 3D significantly improves the performance of moving under constraints functionality that now runs five times faster than previously, as measured on a test base extracted from several hundred user scenarios of LEDAS customers. This functionality is used in the context of assembly design and kinematics simulation applications, where a mechanical assembly is composed of 3D parts linked with assembly constraints or kinematic joints. LGS 3D 1.5 is able to follow a user’s trajectory as close as possible while keeping hundreds of constraints/joints satisfied in real time, so it serves as a base for efficient modeling of large assemblies in CAD/CAM/CAE applications.

LGS 3D performance on static constraint solving (model updating functionality) has been improved by 30%, as measured on a test base of 3,000 industrial parametric models.

LGS 3D 1.5 also provides new integration possibilities for CAD/CAM/CAE developers. Its new thread-safe code solves an arbitrary number of parametric models simultaneously. The Lege'n'd 3D demo application is moved to OpenCASCADE 6.3 version.

The robustness of LGS 3D has been proven by its integration into several industrial software packages including ADEM Assembly by ADEM Technologies and ClassCAD by AWV. More than 4,000 users worldwide appreciated the added value of LGS 3D during beta testing of the Driving Dimensions plugin for Google SketchUp, a popular 3D modeling software application. This plugin combines direct geometry editing with parametric modeling capabilities and implements the so-called variational direct modeling approach. Everyone can use Driving Dimensions for free to test the power of LGS 3D. For more details visit www.DrivingDimensions.com.

See below animated examples that demonstrate progress in LGS 3D moving under constraints functionality.

For the full list of changes see Release Status page.